/*#include <stdio.h>
#include <math.h>

int main(void) {
  int X, Y, N;
  double r;

  while (1) {
    scanf ("%d %d %d %lf", &X, &Y, &N, &r);
    if (X == 0 && Y == 0 && N == 0 && r == 0)
      break;

    if (X * (r / 12.0) / 100 >= Y) {
      printf("NO\n");
      continue;
    }

    int i;
    for (i = 1; i <= N * 12; i++) {
      X += X * (r / 12.0) / 100;
      X -= Y;
      if (X <= 0) {
        printf("YES\n");
        goto nextStep;
      }
    }

    if (X > 0) printf("NO\n");
    else printf("YES\n");
    printf("NO\n");

    nextStep:;
  }

  return 0;
}*/


#include <stdio.h>
#include <math.h>

int main(void)
{
	int X, Y, N;
	double r;

	while(1) {
		scanf ("%d %d %d %lf", &X, &Y, &N, &r);
    		if (X == 0 && Y == 0 && N == 0 && r == 0)
		      break;
		double p=1+r/1200.0;
if(!(r > 0)) {
	int t=ceil((double)X/(double)Y);
	if(t<=12*N) printf("YES\n");
	else printf("NO\n");
}
else {
	double zustatek=((double)X)*pow(p, 12.0*N)-((double)Y)*(pow(p,12.0*N)-1)/(p-1.0);
		
		if(zustatek>0) printf("NO\n");
		else printf("YES\n");
}
	}


	return 0;
}